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Evaluation of chemical composition of Byrsocarpus dinklagei: An uncommon indigenous spice consumed in south-eastern Nigeria
No full textBackground: Spices especially in form of herbs and leaves, are commonly used in food preparation in eastern Nigeria. However, they are not usually accounted for in the nutritional content of foods. Byrsocarpus dinklagei is one of the uncommon aromatic spices added to cooked food for enhanced organolpetic properties and health purposes. Objective: This study evaluated the proximate, vitamins and phytochemical compositions of B. dinklagei (efu) spice. Methods: Seeds of B. dinklagei were dried in a cabinet dryer at 70oC to a constant weight and pulverized to powder. The ground powder was evaluated for proximate, vitamins and phytochemical compositions using standard methods. Data obtained was analyzed for mean and standard deviation. Results: The results showed that the spice contained 4.14% protein, 20.54% moisture, 2.19% fat, 1.83% ash, 1.94% crude fiber and 74.71% carbohydrate. Byrsocarpus dinklagei seeds powder contained 19.60 mg/100g of vitamin B2, 9.09 mg/100g vitamin C and 1.60 mg/100g of beta carotene. The mineral contents per 100g were 3.3mg Mg, 14.10 mg K, 0.9mg Na, 1.0 mg Ca, 212.0mg Mn, 598.0 mg Fe, 72 mg Cu and 144.0 mg Zn. The identified phytochemical content of B. dinklagei were 8.50 mg/100g of tannin, 115.10 mg/100g of alkaloid, 57.60 mg/100g of flavonoid, 21.00 mg/100g of saponin, 41.1 mg/100g of phytate and 25.00 mg/100g. Terpene profilr showed the presence of alpha-pinene, beta-myrcene, delta 3-carene, limonene, and rho-cymene as the main terpenes detected in the spice with a total terpene content of 50.70 mg/100g. Conclusion: The spice powder is a rich source of micronutrients and phytochemicals of biological significance
Nanofiber electrospun membrane based on biodegradable polymers for biomedical and tissue engineering application
No full textDisengagement detection within an intelligent tutoring system
No full textThis paper describes a novel automated disengagement tracing system (DTS) that detects mind wandering in students using AutoTutor, an Intelligent Tutoring System (ITS) with conversational agents. DTS is based on an unsupervised learning method and thus does not rely on any self-reports of disengagement. We analyzed the reading time and response accuracy of 52 low literacy adults who interacted with AutoTutor to learn reading comprehension strategies. Our results show that students completing a lesson with 20 questions tend to start mind wandering at the 11th ~15th question. Question chunks with mind-wandering have an accuracy of 20%, in contrast to 70% in accuracy for non-mind wandering
Quantifying the impacts of land-use and climate on carbon fluxes using satellite data across Texas, U.S.
No full textClimate change and variability, soil types and soil characteristics, animal and microbial communities, and photosynthetic plants are the major components of the ecosystem that affect carbon sequestration potential of any location. This study used NASA\u27s Soil Moisture Active Passive (SMAP) Level 4 carbon products, gross primary productivity (GPP), and net ecosystem exchange (NEE) to quantify their spatial and temporal variabilities for selected terrestrial ecosystems across Texas during the 2015-2018 study period. These SMAP carbon products are available at 9 km spatial resolution on a daily basis. The ten selected SMAP grids are located in seven climate zones and dominated by five major land uses (developed, crop, forest, pasture, and shrub). Results showed CO2 emissions and uptake were affected by land-use and climatic conditions across Texas. It was also observed that climatic conditions had more impact on CO2 emissions and uptake than land-use in this state. On average, South Central Plains and East Central Texas Plains ecoregions of East Texas and Western Gulf Coastal Plain ecoregion of Upper Coast climate zones showed higher GPP flux and potential carbon emissions and uptake than other climate zones across the state, whereas shrubland on the Trans Pecos climate zone showed lower GPP flux and carbon emissions/uptake. Comparison of GPP and NEE distribution maps between 2015 and 2018 confirmed substantial changes in carbon emissions and uptake across Texas. These results suggest that SMAP carbon products can be used to study the terrestrial carbon cycle at regional to global scales. Overall, this study helps to understand the impacts of climate, land-use, and ecosystem dynamics on the terrestrial carbon cycle
Phosphorus and Nitrogen Adsorption by Clinoptilolite Zeolite Coated with Iron-Oxide
No full textClinoptilolite zeolite coated with hydrous ferric oxide (FeZeo) may improve nutrient retention when blended into sand-based root zones. The objective of this study was to evaluate the effects of nutrient-charged FeZeo on nitrogen (N) and phosphorus (P) leaching and on growth of creeping bentgrass (Agrostis palustris Huds.). FeZeo was pre-loaded with 255 mg kg−1 N and 224 mg kg−1 P using a water-soluble fertilizer. Then, root zone mixes (RZM) containing 0, 5, 10, and 20% fertilizer-loaded FeZeo were packed into lysimeters and seeded with creeping bentgrass at a rate of 49 kg ha−1. RZMs with 20% FeZeo received no additional fertilization whereas those containing 0, 5, and 10% FeZeo received four additional fertilizer applications during the next 8 months so that the cumulative N and P rates for every lysimeter were equivalent to 149 kg ha−1 and 131 kg ha−1, respectively. Lysimeters were irrigated every 2 to 3 days and leachate was collected and analyzed. Compared to putting green sand, the 5, 10 and 20% FeZeo treatments reduced the quantity of leached P by 96.2%, 91.3%, and 90.3%, and the quantity of leached N by 88.6%, 82.7% and 76.7%, respectively. Results suggest that pre-fertilized FeZeo applied to sand-based root zone mixes at 5 to 10% can significantly reduce nutrient leaching while maintaining acceptable plant growth, but higher rates of FeZeo can reduce plant growth. An alternative use for higher rates of FeZeo might include a filtering material for agricultural tile drainage. Abbreviations: cation exchange capacity (CEC), electrical conductivity (EC), iron-oxide coated clinoptilolite zeolite FeZeo, nitrogen (N), RZM, root zone mix
Active Control of a Forced Mindlin-type Beam
Get PDFIn this study, optimal dynamic response control of a forced Mindlin-type beam is studied. The beam under consideration, which consists of central host layer and two piezoelectric patch actuators bonded on perfectly to both sides of the beam. It is assumed that the beam is subject to the forcing function, initially at rest and undeformed. Hence, a forced Mindlin-type beam is considered for active vibration control. For this aim, well-posedness and controllability of the system are presented. Performance index functional to be minimized by using minimum level of control voltage consists of a weighted quadratic functions of displacement and velocity of the beam and also includes a quadratic functional of the control function as a penalty term. In order to obtain the optimal control function, an adjoint variable satisfying the adjoint equation corresponding to state equation is defined. A maximum principle is introduced and optimal control function is obtained by means of maximum principle. It is not sensible to use the Linear Quadratic Regulator and Linear Quadratic Gaussian methods to solve the control problem in this paper since the equation under consideration also includes Heaviside function and its spatial derivatives due to existence of piezoelectric patch actuators. Therefore, maximum principle is employed in the present paper Also, by using maximum principle, control problem is reduced to solving a system of partial differential equations including state, adjoint variables, which are linked by initial, boundary and terminal conditions. The solution of this system is obtained by using MATLAB. Numerical results are presented in tables and graphical forms to demonstrate the effectiveness and capability of the introduced control algorithm
Some Midpoint Type Inequalities for Riemann Liouville Fractional Integrals
Get PDFIn the literature, there are a lot of studies about midpoint type inequalities for Riemann Liouville Fractional Integrals. But for most of them, the right and left fractional integrals are used together. In this paper, we give three new Riemann-Liouville fractional midpoint type identities for differentiable functions by using only the right or the left fractional integral. From these identities, we obtain some new midpoint type inequalities for harmonically convex functions by applying power mean and Hölder inequalities
Optimal Homotopy Asymptotic Solution for Thermal Radiation and Chemical Reaction Effects on Electrical MHD Jeffrey Fluid Flow Over a Stretching Sheet through Porous Media with Heat Source
Get PDFIn this paper, the problem of thermal radiation and chemical reaction effects on electrical MHD Jeffrey fluid flow over a stretching surface through a porous medium with the heat source is presented. We obtained the approximate analytical solution of the nonlinear differential equations governing the problem using the Optimal Homotopy Asymptotic Method (OHAM). Comparison of results has been made with the numerical solutions from the literature, and a very good agreement has been observed. Subsequently, effects of governing parameters of the velocity, temperature and concentration profiles are presented graphically and discussed
Analysis of an Eco-Epidemiological Model under Optimal Control Measures for Infected Prey
Get PDFThis paper examines the analysis of an eco-epidemiological model with optimal control strategies for infected prey. A model is proposed and analyzed qualitatively using the stability theory of the differential equations. A local and global study of the model is performed around the disease-free equilibrium and the endemic equilibrium to analyze the global stability using the Lyapunov function. The time-dependent control is introduced into the system to determine the best strategy for controlling the disease. The results obtained suggested the separation of the infected population plays a vital role in disease elimination
Generalized Bagley-Torvik Equation and Fractional Oscillators
Get PDFIn this paper the Bagley-Torvik Equation is considered with the order of the damping term allowed to range between one and two. The solution is found to be representable as a convolution of trigonometric and exponential functions with the driving force. The properties of the effective decay rate and the oscillation frequency with respect to the order of the fractional damping are also studied. It is found that the effective decay rate and oscillation frequency have a complex dependency on the order of the derivative of the damping term and exhibit properties one might expect of a thermodynamic Equation of state: critical point, phase change, and lambda transition